Java design patterns are reusable solutions to common problems in software design. They provide a structured approach to coding and are widely used in the Java community. Here's an overview of key categories:

1. Creational Patterns 🧱

These patterns focus on object creation mechanisms.

  • Factory Method: Encapsulates object creation logic.
  • Abstract Factory: Provides an interface for creating families of related objects.
  • Singleton: Ensures a class has only one instance.
  • Builder: Separates construction of complex objects from their representation.
  • Prototype: Uses prototype objects to create new objects.

📌 Tip: Use the Factory Method pattern when you need to decouple object creation from usage.

2. Structural Patterns 🔗

These patterns deal with object composition and structure.

  • Adapter: Matches interfaces of different classes.
  • Decorator: Adds responsibilities dynamically.
  • Composite: Composes objects into tree structures.
  • Facade: Simplifies complex subsystems.
  • Proxy: Controls access to a real subject.

🎯 Example: Adapter Pattern is useful for integrating legacy systems with new interfaces.

3. Behavioral Patterns 🔄

These patterns handle communication between objects.

  • Observer: Defines a one-to-many dependency.
  • Strategy: Encapsulates algorithms within objects.
  • Command: Encapsulates requests as objects.
  • State: Allows objects to change behavior based on state.
  • Template Method: Defers algorithm definition to subclasses.

🚀 Bonus: Explore Strategy Pattern for dynamic behavior implementation.

4. Additional Resources 📚

Observer
Strategy_Pattern